Gus Poyet described Wednesday night's fixture at Old Trafford as "quite a strange game". Sunderland's manager gave the distinct impression that he harbours mixed feelings about a Capital One Cup semi-final second leg staged at a time when his struggling side remain stuck in the Premier League's relegation zone.

His players hold a fragile 2-1 lead from the first leg but Poyet knows that reaching Wembley and slipping into the Championship would not only constitute a most unwanted double but appear to be a case of rank incompetence. The alternative scenario involves Sunderland exposing Manchester United's current frailties before, bolstered by their impending big final date with Manchester City, potentially shooting up the table.

"In normal conditions, if Manchester United were in the top four and we were mid-table it would probably be a bigger game for us," Poyet acknowledged. "It would be massive and a unique opportunity. Now because of where we are in the League, it makes it quite strange. But both teams have a chance to change the course of their season."

The Uruguayan will be fascinated to see how United react to the stress of what he said "might be a must-win game" for David Moyes. "Even a goal down everybody in the world will be expecting them to win at home," he said. "But there's more pressure on them.

"David took the most difficult job in the world. After Sir Alex Ferguson left it was always going to be the most difficult job. It's a big change. It's not like changing managers at any other club. I hope David's given time to turn things round; he deserves that for what he did at Everton.

"If somebody needs to win this game it's Manchester United but for us it's a great opportunity and I wouldn't like to give it away cheaply. If we don't make it I want it to be because Manchester United were very good not because we gave them it. We can't aim for 0-0; we need to try to score a goal."

Poyet is never quite sure what sort of football his infuriatingly inconsistent side will produce. Last Saturday, a week after an impressive 4-1 win at Fulham, Sunderland were appalling for an hour at home to Southampton but ended up, semi-miraculously, rallying from 2-0 down to force a draw.

"If we start like we did the other day, it could be over after 20 minutes," Poyet said. "Against Southampton we were not playing as a team, not reading the game, not aware of our surroundings and not reacting. We were second best at everything, technically, tactically, mentally, physically, reactions, speed. There was so much difference between the teams it was scary. But somehow we got out of it."

The 9,000 supporters streaming south-west across the Pennines on Wednesday will expect an infinitely better performance. "That 9,000 are going just confirms things for me," Poyet said. "It confirms how big football is for this city and these fans. I'm feeling that every day here. They deserve something to cheer about."

The Uruguayan spoke with the authority of a man who has conducted extensive market research. "I am living in Sunderland and, because I can't cook, I go to restaurants all the time and I meet people every day and I know how much this club means to them.

"People talk about Wembley and how important it is to win this game and they don't want to know about the league. I'm the one bringing the league into the equation. They just want to go to Wembley.

"There's no better connection for a player and supporters than to win trophies. Celebration brings people together and then you feel for the club in a different way. I would like my players to have that feeling. I want these players to remember this club from the inside."

He also wants Sunderland to beat Stoke at the Stadium of Light on Wednesday week. "It will be easy to motivate the players for the semi-final," Poyet said. "The one that will be different is Stoke."

In recent weeks balancing League and cup priorities has been further complicated by his possession of only one senior fit goalkeeper. Now, though, Vito Mannone has an understudy to replace the injured Keiren Westwood after Almería, the Spanish club, rescinded Oscar Ustari's contract, allowing the 27-year-old Argentina keeper to sign for Sunderland until the end of the season.